The present invention relates to a footgear with replaceable flap elements, particularly but not exclusively usable for skiing.
Conventional ski boots are generally constituted by at least one quarter associated with a shell.
Both the shell and the quarter are usually manufactured by injecting thermoplastic material and are secured on the foot and on the leg by means of adapted tensioning devices for cables, straps or racks.
An important problem in designing the ski boots is that of optimally securing the foot inside the boot and at the same time achieving an optimum comfort for the skier.
German patent no. 2031751 filed on Jun. 26, 1970 discloses a shell having a region, located at the upper and lower metatarsal regions, which is open and can be closed by means of an adapted tongue provided with levers for securing it to the shell.
The shell also has, at the upper region of the malleoli, adapted notches suitable to allow a deformation of the upper quarter with respect to the shell.
This known type of boot, however, has a few problems. On one hand, the tongue and the shell are connected by means of hinges which create localized pressure points for the foot.
On the other hand, the tongue cannot be replaced easily when it is worn out, because this would require the drilling of the studs or rivets and subsequent connection, with centering problems. Furthermore, also the levers must be replaced because they are connected to the tongue, with a considerable increase in cost.
Another problem which in fact occurs in known ski boots is that some parts of the quarter are subject to wear during sports practice, and this makes the boot unaesthetic or unusable.
The rivets generally used to mutually connect elements made of plastic material, or the stitches employed when leather was used, make this replacement operation practically impossible, because of its high costs and also because of the fact that auxiliary devices, such as devices for varying the angle of the quarter with respect to the shell, are usually associated at the studs or guides for cables or other elements are located at said studs.
Italian patent no. 858508 filed on Feb. 26, 1969 discloses a ski boot manufacturing process wherein a rigid thermoplastic material is injected in a mold to form only the lower part of the item of footgear, which is joined to the upper part, made of another soft and semi-elastic material, by means of a melt-stitching with penetration of the materials along the joining line. Any replacement of the element made of soft material is unfeasible because of the high costs and also because of the possible deformation which the lower part, made of rigid thermoplastic material, may have undergone in the course of time.
Furthermore, any replacement would also entail the replacement of all the closure devices associated with the upper part made of soft material.
U.S. Pat. No. 3,609,887, filed on Mar. 18, 1970 discloses a process for manufacturing a ski boot entailing the production of a lower part and of an upper part which can be mutually joined at adapted coupling means.
However, said coupling means are very complicated, because a hinge-like articulation is provided laterally to the upper portion of two parts which constitute the quarter and for the connection of said articulation to an adapted plate which is laterally coupled to the lower part.
The boot thus obtained therefore has considerable problems from the point of view of comfort for the user, as well as aesthetic ones.
As a partial solution, Italian patent no. 162434, filed on Nov. 22, 1973 discloses a footgear, particularly for skiing, comprising a shell and a tongue which extends upward from the front part of the shell and up to the vicinity of the instep region and an intermediate collar element which embraces the median region of the sole of the shell. A longitudinal opening is formed at the tongue on the upper part of the intermediate element and an upper quarter is associated, by means of an articulation, with the intermediate element and with the shell. Closure means are provided on the intermediate element and on the upper quarter.
This boot, too, has a few problems. Any replacement of the intermediate element or of the upper quarter entails the need to unhinge them from the shell which, besides, during sports use, may have undergone deformations which might make watertightness ineffective during recoupling to a new intermediate element or upper quarter.
The cost of this replacement would also be high, due to the operations required to unhinge and recouple the elements.
This same Applicant also filed, on Oct. 13, 1976, an Italian Patent application, no. 28245 A/76, related to a ski boot comprising an upper quarter comprising a first part, which can overlap the shell at the front upper part of the foot, and a second part, which can be secured on the shell above the ankle. The first part is joined to the second part by means of linking portions provided at a pair of pivots protruding from the shell at the ankle.
However, this solution, too, has problems, because any replacement of the upper quarter entails treatment steps which provide for the uncoupling of said upper quarter from a protrusion or pin which protrudes from the shell, from the elastic membrane and from the pivots. Furthermore, this replacement would affect the entire structure of the upper quarter, and would thus have hardly negligible costs in relation to any small deformations or wear undergone in localized regions of said upper quarter.
A similar problem is also observed in the ski boot disclosed in U.S. Pat. No. 4,841,650, because the upper quarter is constituted by a single element associable with the shell.
The upper quarter furthermore interacts with several devices which might also require replacement in case of fatigue produced during sports practice.
Furthermore, the mentioned possibility of dividing the upper quarter into two parts entails, due to the considerable interaction between said parts during sports practice, the possibility of having to replace both parts, thus increasing costs for the operations.
Furthermore, the upper quarter and the shell are mutually connected at adapted protrusions which project from the lower perimetric edge of said upper quarter and are located at the adapted slots defined on the shell. These points are water infiltration regions and require, for correct waterproofing, a glueing which would thwart any replacement of the part.